Composition for improving wrinkle resistance in fabrics, wrinkle-reducing active ingredient as used in such a composition, and cartridge containing such composition

ABSTRACT

The invention relates to a composition to improve wrinkle resistance in fabrics, comprising: a wrinkle-reducing active ingredient, comprising at least one fusible elastomer and cross-linked particles, and a liquid carrier for carrying the active ingredient. The invention also relates to a wrinkle-reducing active ingredient as used in such a composition and a cartridge for an iron containing such a composition.

The invention relates to a composition for improving wrinkle resistancein fabrics, comprising: a wrinkle-reducing active ingredient, comprisingat least one fusible elastomer, and a liquid carrier for carrying theactive ingredient. The invention also relates to a wrinkle-reducingactive ingredient as used in such a composition. The invention furtherrelates to a method of improving wrinkle resistance in a fabric by theuse of such a composition.

In-Wear Wrinkle Resistance (IWWR), as the name suggests, means theproperty of a given fabric, e.g. cotton, which enables it to resist theformation of wrinkles, especially during wearing of the fabric. IWWR canbe assessed by measuring the ability of a given fabric to resist theformation of wrinkles. Wrinkle resistance is generally assessed byWrinkle Recovery Angle (WRA) tests. A well-known standard test is theAATCC method 66-1998. Such tests assess the ability of fabric which isset in a flat state to recover this flat state after being folded andsubjected to a temporary load, preferably 500 g during 60 s, and thenreleased. The assessment is carried out by measuring the recovered angle(WRA) after a given time (commonly 5 minutes). The greater the angle,the better the recovery. Angles are measured in, both, the warp and weftdirections and added up to give a final result of the assessment. Aperfectly elastic material would give a WRA of 360 degrees. A perfectlyviscous material would give a WRA of 0 degrees.

Compositions for reducing wrinkle formation in fabrics are alreadyknown. The American patent publication U.S. Pat. No. 5,532,023discloses, for example, a wrinkle-reducing composition which can beapplied to fabrics. The composition comprises a wrinkle-reducing activeingredient, comprising an effective amount of silicone, and an effectiveamount of film-forming polymer, which active ingredient is dispersed ina liquid carrier. In particular, the disclosed composition is adapted toimpart a lubricating property or increased gliding ability to fibers infabric, particularly clothing. This gliding effect between the fibers iscaused in particular by the silicone. A deformation of the clothingreduces the resistance between the fibers of the clothing, which resultscommonly in a decreased energy dissipation at the fibers and (thus) alsoa relatively good and easy contra-deformation (recovery) of the fiberstowards the original state. However, decreasing the resistance betweenthe fibers of the clothing will also facilitate the formation of awrinkled state of the clothing. Application of the disclosed compositionto clothing leads commonly to a WRA of up to about 200 degrees.

It is an object of the invention to provide a novel composition whichimproves wrinkle resistance in fabrics, without facilitating theformation of a wrinkled state of the fabrics.

This object of the invention is achieved by a composition as mentionedin the opening paragraph, characterized in that the wrinkle-reducingactive ingredient further comprises a filler which is at least partlyprovided with chemically crosslinked particles. The use of a filler withcrosslinked particles in combination with a fusible elastomer willcommonly lead to a significantly higher recovery of the fabric than therecovery according to the prior art. Application of the compositionaccording to the invention will generally lead to a WRA of significantlyabove 200 degrees. In particular, the active ingredient according to theinvention will form elastic bridges between the fibers of the fabricunder normal conditions, so that deformation of the fabric will commonlyresult in a lasting recovery of the fibers in their originalorientation. Thus, the crosslinked particles provide—in combination withthe fusible polymer—an elastic bond between the fibers with a certainmemory, which enables it to recover relatively easily after bending orcreasing of the fibers. Preferably, the crosslinked particles arecaptured in a matrix of the fusible elastomer. Crosslinked particlesthat may be used are, for example, polybutadiene, natural rubber,crosslinked silicones such as crosslinked polydimethylsiloxane, andpolymeric microfibers. Fusible elastomers used may be, for example,aliphatic polyester polyurethane, aliphatic polyether polyurethane or aacrylate copolymer of butyl acrylate and acrylic acid with a relativelylow glass tmmsition temperature (Tg), preferably in a ratio of 80:20.The liquid carrier used in the composition of the present invention ispreferably an aqueous system. Optionally, in addition to water, thecarrier may comprise another liquid solvent which is well soluble inwater, such as an alcohol.

In a preferred embodiment of the invention, the filler consistsentirely, or at least substantially, of chemically crosslinkedparticles. The elastic property of the crosslinked particles can thus beoptimally utilized. For example, a polydimethylsiloxane like Dow CorningC 1716® may be used, which directly binds itself to the matrix formed bythe fusible elastomer.

In another preferred embodiment, the filler is provided with athermoplast, preferably polymethylmethacrylate (PMMA). In this mannerthe filler consists in particular of particles comprising at least twocompositions, i.e. the crosslinked composition which provides an elasticproperty to the filler, and a non-crosslinked composition formed by athermoplast for improving the binding of the filler to the matrix formedby the fusible elastomer. The filler according to this embodiment can beconstructed in a laminar way, such that each layer consists of specificcompositions. Thus it is also possible to provide, for example, a socalled ‘core-shell’ filler particle, which consists at leastsubstantially of an elastic core formed by said crosslinked composition,which core is surrounded by a substantially non-elastic shell formed bysaid thermoplastic composition. As crosslinked composition for the core,for example Estapor® carboxylated micro-spheres of SBS copolymer ofMerck, may be used.

Preferably, particles of the filler have an at least substantiallyspherical shape. In a preferred embodiment, however, particles of thefiller have an at least substantially fibrous shape, such asmicro-fibers. Other shapes may also be used to give the desiredanti-wrinkle effect.

The content of the active ingredient in the liquid carrier is between 2and 60% by weight. Between these values a good dispersion of the activein the liquid carrier can be obtained and maintained. If said percentageof 60 percent is (significantly) exceeded, commonly a sticky,non-controllable dispersion is obtained. Preferably, the filler contentin the active is between 10 and 30% by weight, preferably 20% by weight.In this way a stable matrix of fusible elastomer can be obtained, inwhich the crosslinked fillers are captured.

In an embodiment of the composition according to the present invention,the elastomer has a softening temperature between 50 and 100° C. in thepresence of water. Easy softening of the elastomer at an increasedtemperature results commonly in an easy provision of the yarns of thefabric with the composition according to the invention. The viscosity ofthe softened composition is relatively very low, which means that, forexample, during ironing of said fabric, the polymers do not interferewith the wrinkle removal of the fabric as long as the fabric isrelatively hot. When the fabric cools down, the composition according tothe invention solidifies to form an elastic film around and between theyarns or individual fibers, thereby inducing a degree of elasticity inthe treated fabric. This in turns improves the WRA value substantially.

In another preferred embodiment of the composition according to thepresent invention, the active ingredient is removable by washing. If afusible elastomer is applied, which is removable by washing, commonlythe active ingredient as a whole, including the crosslinked fillers, iswashed out. An example of a fusible elastomer which is removable bywashing consists substantially of a copolymer of butyl acrylate andacrylic acid, preferably in the ratio of 80:20. However, it is alsoconceivable to apply a more durable active ingredient, which is not, orat least hardly, removable by washing. Examples of such durable activeingredients are aliphatic polyester polyurethane (Permutex® RU 13-011)and aliphatic polyester polyurethane (Permutex® RU-4049).

The composition according to the invention is preferably provided withadditives, such as surfactants, perfumes, anti-bacterial additives,silicones for improving gliding between the fibers of the fabric, etc.,as long as the additive does not interfere with the primary function ofthe polymer. The use of additives in a composition according to theinvention can be very suitable when the compound is applied to a fabricby means of a domestic appliance, such as a washing machine or an iron.

The invention also relates to a wrinkle-reducing active ingredient asused in said composition and to a cartridge containing said compositionand suitable for use in an iron.

The invention further relates to a method of improving wrinkleresistance in a fabric by use of said composition, comprising the stepsof: A) applying the composition to the fabric, B) removing the wrinklesin the fabric, and C) permitting the liquid carrier to evaporate atleast partly. The amount of active ingredient typically applied,particularly sprayed, onto the fabric is preferably from about 0.1 toabout 10% by weight, more preferably from about 0.5 to about 5% byweight of the fabric. Once an effective amount of composition has beensprayed onto the fabric, the fabric is stretched or smoothed by handaccording to step B). After the effective amount of composition has beenapplied to the fabric and preferably stretched, the liquid, inparticular moisture, is permitted to evaporate at least substantially.The evaporation may occur in a passive way as well as in an active wayby increasing the temperature of the fabric. Evaporation of the moistureis commonly relevant, as the particles of the fusible elastomer willstick together and thus form a solidified sheath around the fibers andyarns of the fabric. Furthermore, evaporation of moisture will commonlyalso result in stress relaxation in the yarns of the fabric. A decreasein the stored energy will maintain the fabric in its set, i.e. flat,state.

Preferably, the application of the composition to the fabric accordingto step A) is realized by means of a domestic appliance. Examples ofsuch domestic appliances are a washing machine, an iron provided with acomposition spraying reservoir, and other spraying devices for acomposition according to the invention.

In a preferred embodiment of the invention, the removal of the wrinklesin the fabric according to step B) is realized by means of an iron at anincreased temperature compared with an ambient temperature. In this waystep C) will commonly be applied during application of step B). Thus,the increased temperature will lead both to an accelerated evaporationof applied liquid and to a softening of the fusible elastomer. Coolingdown of the fabric results commonly in an elastic protective layer beingformed around the stretched yarns of the fabric, such that the layersare bound to each other by elastic bridges. Deformation of the fabricafter application the method according to the invention will temporarilylengthen said elastic bridges, which attempt to bring the yarns into,their original stretched, non-wrinkled state during a certain time.

The invention may be further illustrated with the followingnon-limitative examples and a single figure showing an iron with acartridge containing the claimed composition.

EXAMPLE 1

A 12.5% (by weight) dispersion of a mixture of Permutex RU-4049® 40%aqueous emulsion and Estapor® 10% latex (175-225 nm core-shell particlesconsisting of a crosslinked elastomeric polystyrene-co-butadiene coreand a carboxylated shell) in water was prepared by mixing theaforementioned emulsions with water in a ratio such that the amount ofEstapor® was 10% with respect to the Permutex RU-4049®, (i.e. 1:9) hence1.25% with respect to the total weight of the dispersion. Thiscomposition was then sprayed onto a piece of fabric (cotton type 407)such that the total pick-up with respect to the fabric weight was 40%.This led to an additive pick-up of 5% of the fabric weight, when thefabric was dry. The fabric was then ironed with an iron set to atemperature suitable for cotton, until the fabric was dry. Afterconditioning of the fabric for 24 hours, the WRA was measured for apiece of fabric 40 mm×15 mm in both the warp and weft directionsaccording to the standard AATCC method 66-1998. The average WRA valueobtained from fabrics treated as above was compared with WRAmeasurements carried out on fabrics that were ironed without theapplication of any additives (reference value) as well as fabrics whichwere ironed after the application of 5% of fabric weight of PermutexRU-4049® only. The results are summarized in the Table below, wherePermutex RU-4049® is referred to as RU-4049 and the Estapor® latex isreferred to as Estapor. Treatment WRA Reference 140° 5% RU-4049 200° 5%(RU-4049 + Estapor 9:1) 210°

EXAMPLE 2

A 12.5% (by weight) dispersion of a mixture of Permutex RU-4049® 40%aqueous emulsion and Dow Corning 1716® 30% aqueous microemulsion(crosslinked PDMS, polydimethylsiloxane) in water was prepared by mixingthe aforementioned emulsions with water in a ratio such that the amountof Dow Corning 1716® was 20% with respect to the Permutex RU-4049® (i.e.1:4), hence 2.5% of the total weight of the dispersion. This compositionwas then sprayed onto a piece of fabric (cotton type 407) such that thetotal pick-up with respect to the fabric weight was 40%. This led to anadditive pick-up of 5% of the fabric weight, when the fabric was dry.The fabric was then ironed with an iron set to a temperature suitablefor cotton until the fabric was dry. After conditioning of the fabricfor 24 hours, the WRA was measured for a piece of fabric of 40 mm×15 mmin both the warp and weft directions according to the standard AATCCmethod 66-1998. The average WRA value obtained from fabrics treated asabove was compared with WRA measurements carried out on fabrics thatwere ironed without the application of any additives (reference value)as well as fabrics which were ironed after the application of 5% offabric weight of Permutex RU-4049® only. The results are summarized inthe Table below, where Permutex RU-4049® is referred to as RU-4049 andthe Dow Corning 1716® is referred to as DC-1716. Treatment WRA Reference140° 5% RU-4049 200° 5% (RU-4049 + DC-1716 4:1) 225°

The Figure shows an example of an iron with an exchangeable reservoirfor containing the claimed additive composition. The iron comprises ahousing 1, a sole plate 2, a heating element 3 for heating the soleplate, an exchangeable reservoir for containing the additive composition5, and a spraying nozzle means 6. The exchangeable reservoir 4 may be akind of cassette or cartridge with a hard synthetic resin housing. Thebottom 7 of the exchangeable reservoir 4 is provided with an outlet 8for the composition S. A coupling piece 9 is connected at the lower sideof the bottom 7, which coupling piece has a duct 10 of which an inlet isin communication with the outlet 8 of the reservoir 4 and of which anoutlet terminates in an outlet tube 11. The coupling piece 9 may beintegral with the cartridge in a first preferred embodiment. The ironcomprises a delivery system 12 for delivering the composition 5 from theexchangeable reservoir 4 to the nozzle means 6 in order for it to besprayed on the cloth to be ironed. The delivery system comprises a firstchannel 13, an outlet thereof being connected to an inlet of an electricpump 14 arranged inside the housing of the iron, and a second channel15, an inlet thereof being connected to an outlet of the pump 14. Aninlet of the channel 13 is provided with a coupling sleeve 16 forcoupling to the outlet tube 11 of the coupling piece 9. An outlet of thesecond channel 15 is provided with a coupling sleeve 17. According tothe invention, the exchangeable reservoir 4 is provided with the nozzlemeans 6. The nozzle means comprises a nozzle tube 18 terminating in anozzle 19 having an aperture 20. An inlet of the nozzle tube forms acoupling tube 21 for coupling to the coupling sleeve 17 of the secondchannel 15. The exchangeable reservoir 4 can be inserted into a cavity22 of the iron. A pivotable cover 23 can close the cavity 22. When aspray of composition is desired, the user starts the pump 14 by pressinga knob 24. The pump sucks the additive composition 5 from the reservoir4 into the channel 13 and pumps it via the channel 15 and the nozzletube 18 towards the nozzle 19. The exchangeable reservoir 4 includingthe nozzle means 6 can be implemented as a disposable cartridge, so thatevery new cartridge is provided with clean nozzle means.

1. Composition to improve wrinkle resistance in fabrics, comprising: awrinkle-reducing active ingredient, comprising at least one fusibleelastomer, and a liquid carrier for carrying the active ingredient,characterized in that the wrinkle-reducing active ingredient furthercomprises a filler which is at least partly provided with chemicallycrosslinked particles.
 2. Composition according to claim 1,characterized in that the filler consists entirely of chemicallycrosslinked particles.
 3. Composition according to claim 1,characterized in that the filler is provided with a thermoplast,preferably polymethylmethacrylate (PMMA).
 4. Composition according toclaim 1, characterized in that the content of the active ingredient inthe liquid carrier is between 2 and 60% by weight.
 5. Compositionaccording to claim 1, characterized in that the filler content in theactive ingredient is between 5 and 50% by weight, preferably between 10and 20% by weight.
 6. Composition according to claim 1, characterized inthat the elastomer has a softening temperature between 50 and 150° C. inthe presence of water.
 7. Composition according to claim 1,characterized in that the composition is provided with additives,preferably a surfactant or a perfume.
 8. Wrinkle-reducing activeingredient as used in a composition according to claim
 1. 9. Cartridgedesigned for an iron and containing a composition according to claim 1.